Light source device and diplay device

Abstract

There are provided a light source device and a display device which do not generate a wrinkle on an optical sheet even if the optical sheet is held on an LED substrate. A reflection sheet is disposed between each of head portions possessed by a rivet, a positioning rivet and a support rivet and one surface of an LED substrate where an LED is mounted, and a gap in a direction of a sheet thickness is provided between the head portion of each of the rivets and the reflection sheet. In the case in which a sudden thermal change is caused, therefore, the reflection sheet expands or contracts between the head portion of each of the rivets and the reflection sheet so that the wrinkle can be prevented from being generated over the reflection sheet.

Description

[0001]This application is the national phase under 35 U.S.C. §371 of PCT International Application No. PCT / JP2010 / 056808 which has an International filing date of Apr. 16, 2010 and designated the United States of America.BACKGROUND[0002]1. Technical Field[0003]The present invention relates to a light source device provided with a light-emitting element, and a display device which includes the light source device and displays a video image.[0004]2. Description of Related Art[0005]A liquid crystal display device referred to as a thin type such as a liquid crystal television includes a display unit which has, on a right side, a display surface for displaying an image and takes a shape of an almost rectangular parallelepiped, and a light source device disposed on a back side of the display unit for applying light on the display unit, and a diffusion plate and an optical sheet such as a prism sheet are provided between the light source device and the display unit.[0006]The display unit h...

AI Technical Summary

Benefits of technology

[0031]Moreover, it is an object of the present invention to provide a light source device capable of preventing luminance unevenness of illumination light from being caused by a fixture, and a display device including the light source device.

[0076]According to the display device in accordance with the present invention, the dimension from the substrate to the top of the head portion is set to be smaller than the dimension from the substrate to the top of the light-emitting element depending on an application range of light to be applied from the light-emitting element, and the light applied from the light-emitting element is thus prevented reliably from being blocked by the head portion of the fixture. Therefore, it is possible to prevent a display grade from being deteriorated due to the occurrence of aluminous unevenness over the display panel. Moreover, the dimension from the substrate to the top of the head portion is set to be smaller than the dimension from the substrate to the top of the lens depending on a diffusion range of light to be diffused by the lens, and the diffused light is thus prevented from being blocked by the head portion of the fixture. Therefore, it is possible to prevent the display grade from being deteriorated due to the occurrence of a luminous unevenness over the display panel.

Problems solved by technology

Referring to a display device including a display surface having a comparatively large area, however, it is hard to uniformly enhance the luminance characteristic.

However, the backlight device of the CCFL type requires high voltage components such as, for example, the inverter circuit board for discharging the cold cathode fluorescent lamp, the electrodes on the both ends of the cold cathode fluorescent lamp and the like, and it is necessary to maintain a comparatively long insulating distance around the high voltage components.

Therefore, the high voltage components hinder a longitudinal thickness from being reduced.

For this reason, it is impossible to control a lighting operation of the cold cathode fluorescent lamp in a fine area.

Furthermore, a high-speed flashing control for suppressing an animation blur or the like is more disadvantageous as compared with the LED type.

In addition, power consumption is increased because the cold cathode fluorescent lamps are turned ON at a high voltage.

However, the backlight device of the LED type described in Japanese Patent Application Laid-Open No. 2006-114445 has a problem in that when the reflection sheet screwed into one of the surfaces of the light-emitting diode substrate expands or contracts due to a sudden thermal change, wrinkles are generated over the reflection sheet due to the expansion or contraction and an optical characteristic of a liquid crystal display device is thus deteriorated.

Moreover, the backlight device of the LED type has the following problem.

In these cases, so-called luminance unevenness is generated so that a grade of the display device is deteriorated.

Consequently, the other end cannot be inserted into the through hole of the support body, and furthermore, a pressing force acts on the shaft portion of the shaft member so that the rivet is held on the support body.

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